Stereoselektive Synthesewege zu (+)-Biotin aus L-Cystein

Abstract

A novel synthesis of (+)-biotin (vitamin H) via a pathway which avoids separation of enantiomers is described. Starting with L-cysteine, the key intermediate 7 is synthesized in four steps without racemization. In a short reaction sequence 7 is converted into 10 or 14 in an overall yield of 40% and 27%, respectively. Both known intermediates are easily transformed into (+)-biotin.